Supporting member for enameling racks



June 19, 1934. 'r NELSQN 1,963,242

SUPPORTING MEMBER FOR ENAMELING RACKS Filed Sept. 28, 1932 We* LM ATTORNEYS Patented June 19, 1934 SUPPORTING MEMERFoR ENAMEEING RAoKs v i Tom H. lNelson, `Villanova,.-Pfa. Y Applicationseptember 28, 1932,'fseria1NQfs35;1`-65 7 Claims. (Cl. 25-153) :The--present=invention relates lbroadly to the fartwof enameling -andmore especially for. a sup- .port for .use in an enameling furnace.

-Enameling operationsnecessitate supporting in 1 '5 -faf furnace the article to be enameledwith aminimum amount of surface of the article in Contact Withthe support. 4Where all Asurfaces are to be covered With enamel, the article is usually supported upon `Veryne pointed posts or short colg elhumns. Heretofore in the art, these postshave comprised an vintegral part of `a casting wherein 4a cast: plate or bar formed the base of the rack. Itfisgparticularly/ desirable in an enameling oven that thefsupportsvshallbe of heat resisting alloy metal so as to avoid scale because an accumulation of scaleand dirt in the furnace is dangerous since itlmay be carried by convection currents to ythe'suriace of molten. enamel and thus injure or sruinthe coating. Cast racks require individual *120 vfinishing. of the points of the supports While the ventire-raclzmust be handled as a unit since the fpostsvand base` bars oriplates are all cast-as a part of thel same integral casting.

In usingY castl supports, it is diflicultto obtain good results from non-scaling heat resisting alloy and itt is particularly difficult to 'obtain' uniform distribution of alloy lmaterials into the small `posts comprising the supportingmembers.

rAnotherdiiiiculty encountered Withv the racks e30-of the-known -art` is that when theracks were s'heated in the-furnace, the unequalfmasses 'of metal forming the racks heat unequallyvin rate 'of time, and, consequently, the racks Warp and distort under the'severe thermal Work. `This is a qlaseriousmatter, particularly-Where the racks are supporting 'flat plates tobe enameled such-ias "-side plates for the refrigerators, etc. 'These plates llmustbe maintained 4substantially level-on ythe V'top-surfacevi/here the'heavy coating ofI enamel forms the outside finish of the completed plate. :If the racks Warp and disturb the level of the (plates, the enamel Willflovv from the high tothe lower points on the plates and the plates are thereby ruined, ortheenameled plate mayvarp sothat it cannot be straightened Without cracking theI enamel.

'Furthermore' cast metal supporting racks require a substantial amount of metal to form a rack that Will not quickly deteriorate in use. It is not infrequent that the mass of metal in a cast rack greatly exceeds the mass of metal in the article to be enameled. It, therefore, follows that the heat units of the furnace Wasted in heating the rack often exceeds the number of heat units necessary to raise Vthe k,article 7being made -..to vitrifyingf temperature for. the: enamel.

VRacks fmay be,mounte'dforv.movementintany convenient .Way into the .furnace Ysuch as- Aupon trackways or vconveyors, slides k..0r A.other ,con-.50 venient .Waysof transporting theracks-intoand out. of the. furnace. v.These featureslare common yin the art.

The present .invention overcomes `the difficulties of the .known .artby providing racks .wherein pref- 65 eraby -Wrought metal. is used. in..the,place of. cast metal. Preferably, the supporting?,basebarsfor the posts .on pins ,arey made. from sheet material, .of vsubstantially .uniform thickness, .formed Linto. a .hollow member.

This member `may .be .alsoo formed from `tubing ,orrotherwise Preferably, the supportinggbase bars are: triangular. in crosssection. Thevpo'stsror supportingpins arelikewise preferably formed of vwrought.metaltandfare riveted` or Welded.v into Vthefiiat bottom portionof g5 the y base bars.` and the posts extendtthrough .the `upper Wall of these ..base'..bars. The posts, howeverrare* not rigidly. anchored. to the upper `Wall ibut are :securely .,anchored .in the blower uWall AThesefpinsare individually. pointed to -ne pointsgw before being set -inthrelbase..bars onawhich Ythe pins are arranged. tog properly-support fthe. article to. be enameled. ,Where.the...article, isa flatplate,

the Ypoints ioflthese pins` lie ,substantially in a plane, other-wise fthelpoints ofjthe pins fitthe sur-35 face to be supported.

Where' desired, thepins. maybe formed ofr holloW tubing, preferably having .the -same .wall thickness Vas the basefsupports'and withqone end .of the tube collapsed and Welded into a solidgpointnno This form of 4pin presents a structure .wherein all of the metal thicknesses throughoutthe. struc .ture-may Cbeuniform. rIt. is talee-understood that the.. racks in accordance withthepresent `inven- ,tion are constructed fromnon-scaling heat resist- 95 ing metallic alloys, l.such fas. for. example,V chrome steel.

The .present-invention. possesses :many-advantages overthecpriorart. Some *of nthese fadivantagesfarethat the pins dol not tend. .to-warp `100 or bend since theyfare-made offworked metal, the

f grain.. and density of the metal` ismuch more funiform-ly `.distributed than: in cast metal. Furthermore, there is little tendency for temperature reactions to tend to cause the pins to break away ,1105 from the base bars. The pins being riveted or Welded or otherwise secured to the lower member of the base bar, have a movement relative to the place where these pins pass through the upper member of the base bars and thus while the pins i110.

ferred form, therefore, it is to be understood that the present invention maybe-embodied in structures other than those specifically shown herewith, and the disclosure herewith is to be understood as illustrative and not in the limiting sense.

Fig. 1 illustrates a detail view of a part of a rack in accordance with the present invention showing a part broken away. f

Fig. 2 illustrates a section built upto support flat plates on the tips of the posts.

Fig. 3 is a modification ofthe invention'. Referring to the drawing and more especially 'lto Fig. l, which illustrates a preferred form of 25 Y the present invention, the bar or main'support preferably comprises a tubular member 1` formed of sheet metal or seamless tubing, the cross section of which is unimportant except that it is desirable this member shall be provided. with a substantially flat lbase 2. Supporting pins are mounted in the base 2 preferably by welding at the point 4. These pins extend through the KupDr portion of the bar but are not anchored at this portion and are freely movable as at the point 5,*so that duringV heating and cooling, a movement may occur between the body of the pin` and the base bar at the point 5. These pins may be solid but in the preferred form comprise tubular members, 6` which are open at the bottom as at7 so 'as to provide an open recess into which the heating gases may freely enter.` In order to prevent pocketing of these heating gases, the tubularv members are preferably provided with openings 8 so that the hot gases may circulate through the tube. In View of the fact that it may be desirable to adjust the height of the tubes'particularly as the points may'tend'to burn off or wear down,

lin the preferred form, the point comprises a conical head 9 provided with a screw threaded body `V lil adapted to be screw threaded into the tubular member 6 and where desired, lock nuts 11 cooperate with a screw threaded portion l() and the ends of the tube 6 to lock the conicalvpoints 9 in adjusted vertical position. These supporting members are usuallyl used as individual bars althoughin certain cases', it may be desirable to make up a grid. Y

Fig; 2 'illustrates a made-,up grid having con- .nected bars 12 and 14 Vand with solid pins 15 extending through the' bars with the bases of the pins welded/or otherwise securely attached 'to the base portions 2 of the grid bars and with these l Ypins extending freely through the upper portion of the grid bars in such manner as toV provide movement between the pins and the bars as explainedwith 'reference to Fig. l.

' f Fig. 3 illustrates a further modification ofthe invention in which points 16 are mounted on ameling oven.

top of the ridge 1'7 of a triangular shaped bar. Preferably, though not necessarily, these points 16 are securely attached by welding or otherwise to the bars 1. y

It is to be understood that the preferred ma terial used for making the Vparts is non-rusting heat-resisting metallic alloys. It is also understood that the present invention is not limited to any particular geometric form of rackor to a specific geometric form of supporting bar.

Having described my invention, I claim:

l. A device of the class described comprising a hollow tubular member having a flat side adapted to operate as a base, and an upstanding mem ber having the lower end thereof anchored to the flat -side of the supporting member, said supporting member being provided with an opening in the upper sidethereof opposite said at side and said upstanding member passing freely through said opening. Y

2. A device of the class described comprising a hollow supporting bar having one side thereof flat, upstanding supports anchored to said flattened side of said bar and extending through openings in the opposite side of said hollow bar, said upstanding supports terminating in points adapted to sustain articles in an enameling yfui-- nace.

3. An article of the class described comprising longitudinally extending base bars formed ofhollow tubing having a flattened side, tubular posts anchored to the flattened side of said hol low tubing with the bottom portion of said posts being open to atmosphere to facilitate passage of hot gases in the said posts.' D

14. A device of the class described comprising an enameling oven rack having longitudinally extending hollow supporting bars, upstanding hollow posts anchored at their lower ends to said supporting bars and extending through open-l ings on the opposite side of said supporting bars, with the base of said posts in open communication with atmosphere, said posts having openings in the side thereof to facilitate passage of hot gases through said posts. f.

5. As an article of manufacture, a supporting bar for fan enameling oven comprising a longitudinally extending hollow member having one side thereof vflattened, and upstanding supports secured to said bar and terminating above said bar to support articles to be enameled in an en- 6. As an article of manufacture, a rack for enameling ovens comprising a hollow supporting bar, a plurality of spaced apart posts secured to a side wall of said supporting bar and extending Vthrough openings in the opposite side of said supporting bar whereby said supporting bar and said posts are free to expand andoontract independently of each other.

7. As an articlev of manufacture, a supporting rack for enameling ovens comprising a supporting member, upstanding posts secured to said supporting member, adjustable points mounted in the upper ends of said posts and being adapted to be raised or lowered to conform with the shape of the article being supported upon said posts.

l TOM H. NELSON.

ist 

